1. Field of the Invention
The present invention relates to a TV, and more particularly, to a method for displaying an electronic program guide (EPG) menu of a TV.
2. Background of the Related Art
Generally, a digital TV receiver, as shown in FIG. 1, includes: a tuner 10 which receives a broadcasting signal; an A/D converter 11 for converting the broadcasting signal received from the tuner 10 into digital broadcasting data; a channel decoder 12 for detecting a pilot signal from the digital broadcasting data to detect a baseband signal and for performing an error correction for the detected signal; a microcomputer 20 for outputting a control signal in accordance with manipulation of a user; a TP analyzer 13 for analyzing a TP signal in the digital broadcasting signal output from the A/D converter 11 to detect audio/video signals under the control of the microcomputer 20; an MPEG audio decoder 24 for decoding the audio signal analyzed in the TP analyzer 13; an MPEG video decoder 25 for decoding the video signal analyzed in the TP analyzer 13; a digital to analog converter (DAC) 30 for converting the digital audio signal decoded by the MPEG audio decoder 24 into an analog signal; a flash ROM (read only memory) 40 where channels and programs are stored; a RAM 41 where temporary data is stored by the operation of the microcomputer 20; and an NTSC encoder 31 for converting the video signal decoded by the MPEG video decoder 25 into an image signal which is displayed on a TV or monitor. Further, an SDRAM 23 is necessary for data processing in the MPEG audio decoder 24 and the MPEG video decoder 25, and a user interface 21 and a CAS interface 22 are necessary for generating an external operation signal for the microcomputer 20.
Generally, the digital broadcasting processes the video signal and the audio signal under the MPEG standard. Particularly, the MPEG standard number for the broadcasting system is ISO/IEC 13818-1, the standard for the video signal is ISO/IEC 13818-2, and the standard for the audio signal is ISO/IEC 13818-3. However, the digital TV receiver in the U.S.A. does not use the audio signal under the MPEG system, and processes it under the standard of DOLBY AC-3.
The tuner 10 receives a Quadrature Phase Shift Keying (QPSK) signal or a Quadrature Amplitude Modulation (QAM) signal from an antenna, and detects and outputs the received signal. The detected signal in the tuner 10 is converted into an intermediate frequency band signal by means of an IF converter (not shown). This is because the detected signal in the tuner 10 is a high frequency signal in a great high frequency band, with which a driving circuit in the digital TV does not deal.
The channel decoder 12 detects the pilot signal in the intermediate frequency signal to detect the baseband signal and converts the baseband signal into a digital signal. Next, it performs a timing recovery corresponding to symbol rate and then performs the error correction. The output signal of the channel decoder 12 is a transport stream packet type signal sequence in a byte unit.
The transport signal sequence, which is standardized in the MPEG-2 system, is a time-multiplexed signal sequence, which is called “transport stream packet”. The transport signal sequence contains a header on which a packet identifier (PID) number is recorded, on the starting of the packet. The PID number is utilized as the information with which the time-multiplexed signal is demultiplexed. Also, the PID number indicates the type of current packet, and if the PID number is analyzed, it is detected whether the current packet is a video packet, an audio packet, or program specific information. Particularly, the digital TV standard in the U.S.A. includes program specific information, that is, program and system information protocol (hereinafter, referred to as ‘PSIP’).
The PSIP includes a master guide table (MGT) where the versions of all the broadcasting program tables are controlled, a terrestrial virtual channel table (TVCT) where the information for channels is stored, a rating region table (RRT) where a rating table of each program is listed, an event information table (EIT) for providing the information on the current broadcasting programs and future broadcasting programs, an extended text table (ETT) for providing detailed information on the current broadcasting programs and future broadcasting programs, and a system time table (STT) for sending current time.
The video and audio standards in the MPEG-2 system are in connection with the signal sequences of the compressed video and audio. Under the MPEG-2 standard, the video signal, the audio signal and the program specific information are all time-multiplexed and transmitted in several transport stream packets. The signal sequences thereof are all discriminated with the PID number.
The TP analyzer 13 analyzes the signal sequence in the transport stream packet with the PID number and applies the analyzed results to each decoders 24 and 25. In more detail, the TP analyzer 13 receives the transport signal sequence received in the tuner 10 and senses the PID number contained on the header of the corresponding signal sequence. Thus, the TP analyzer 13 performs demultiplexing through which the received transport signal sequence is divided into a video signal sequence, an audio signal sequence and a program specific information sequence in accordance with the sensed PID number. Thereby, the TP analyzer 13 applies the video signal sequence to the MPEG video decoder 25, the audio signal sequence to the MPEG audio decoder 24, and the program specific information sequence to the microcomputer 20.
The MPEG video decoder 25 decodes the video signal sequence applied from the TP analyzer 13 and outputs the decoded result to the NTSC encoder 31. The video signal sequence applied from the TP analyzer 13 is the compressed data in the MPEG-2 system. Therefore, the MPEG video decoder 25 decompresses the video signal sequence to restore it to original digital video data.
The MPEG audio decoder 24 decodes the audio signal sequence applied from the TP analyzer 13 and outputs the decoded result to the DAC 30. The audio signal sequence applied from the TP analyzer 13 is the compressed data in the MPEG-1 system. Therefore, the MPEG audio decoder 24 decompresses the audio signal sequence to restore it to original digital audio data.
The DAC 30 converts the digital audio signal applied from the MPEG audio decoder 24 into analog audio signals (R and L) which are processed in an amplifier or speaker. The analog audio signal is output as voice or sound by means of a stereo speaker (not shown).
The NTSC encoder 31 converts the digital video signal applied from the MPEG video decoder 25 into luminance and chrominance signals (Y and C) which are displayed on a general TV or monitor. The luminance and chrominance signals are displayed as video by means of a CRT (not shown).
The microcomputer 20 controls the operation of the digital TV receiver. The flash ROM 40 stores the program necessary for the control of the microcomputer 20, and the DRAM 41 stores the temporary information or data necessary upon the execution of the control operation of the microcomputer 20.
The aforementioned digital TV receives the program specific information signal sequence to provide various kinds of interactive program specific information other than broadcasting programs to a viewer. Such interactive program specific information contain home shopping, newspapers, stock information and so on, which are not obtained in an analog TV. The program specific information signal sequence is a transport stream packet type.
The program specific information system of the TV provides a graphic user interface (GUI) to the viewer for convenient use of the program specific information.
FIG. 2 shows an electronic program guide (EPG) of the program specific information of the GUI type. Referring to FIG. 2, a menu screen 50 includes icons 51 and characters 52 explaining the icons. Most programmers who produce an EPG, produce a menu based on a full screen as shown in FIG. 2.
However, the EPG of the related art digital TV has several problems.
Referring to FIG. 3, in the EPG displayed in the related art digital TV, when the viewer selects a double window mode for simultaneously displaying a broadcasting program screen 60 and an EPG screen 50′, a width of the EPG program screen 50′ becomes smaller. As a result, widths of the characters and icons become smaller, thereby causing the viewer difficulty in discriminating the characters 52′ and icons 51′.
Furthermore, if the icons are displayed with a menu window 50′ of a picture in picture (PIP) mode as shown in FIG. 4, characters 52″ and icons 51″ have smaller widths and lengths, thereby making it difficult for the viewer to discriminate meanings of the characters and icons. Particularly, it is difficult to discriminate meanings of the characters seriously scaled down in their size while meaning of the icons may be discriminated by the viewer to some extent regardless of the double window mode and the PIP mode.